Improved L-gate 4H-SiC MESFETs with partial p-type spacer

An improved L-gate 4H-SiC metal-semiconductor field-effect-transistor with partial p-type spacer (ILP-MESFET) is proposed and its electrical performance modeled. The saturation drain current of the ILP-MESFET is about 20% higher than that of a conventional (C-)MESFET and very close to that of the LP-MESFET at a gate-source voltage of −4 V. The DC bias point of the ILP-MESFET is improved compared with that of a C-MESFET. The gate-source/drain drift region partial p-type spacer can suppress the gate depletion layer extending to source/drain. The simulation resulted in a gate-source capacitance of the proposed structure that is 26% smaller than a LP-MESFET and points to improved RF performance by ILP structures.